The present invention relates to a method and device for guiding an aerodyne on the runway, in bad visibility, particularly during the taxiing phase preceding take off.
Generally, the systems employed for effecting take off in bad visibility use a radioguidance system comprising, a transmitter disposed on the ground at the end of the runway which transmits along the axis thereof a radiobeam defining a radioalignment currently called "localiser" and, a reception system located on board the aerodyne and coupled to a detector adapted for determining the angular aberration between the aircraft and the axis of the runway. This angular aberration may then be used for displaying a guide order, for example by means of a head up type display system, in the form of a conventional trend bar or any other known display system, such as a "PVD" (Para Visual Display) type system or even a system for displaying informations by projecting light symbols on the windscreen of the aerodyne.
Now, at the present time numerous take off runways are not provided with radioguidance systems and cannot be used for poor visibility take offs.
Furthermore, the runways having radioguidance systems become unfit for poor weather take offs, should the transmission of the radioalignment be stopped, for example because of a breakdown or of any other reason.
The object of the invention is then to overcome these problems by means of a method using a completely airborne guidance device for determining a synthetic runway aberration (position of the aerodyne/axis of the runway) without the help of any equipment on the ground.